textproduct: Rapid City

KEY MESSAGES

- Wildfire smoke is expected to linger at least through Friday.

- Isolated chances for storms through Friday, however most places can expect to remain dry.

- Slightly cooler temperatures for Friday, but back into the upper 90s for the remainder of the weekend.

DISCUSSION

(This Afternoon Through Wednesday) Issued at 1141 AM MDT Thu Aug 6 2026

Current Water Vapor and upper air analysis shows ridge over the far western CONUS, while broad upper trough sits over the plains into the Great Lakes region, with northwest flow over the FA. 17Z surface analysis shows a SW-NE oriented surface trough over western SD early this afternoon. Winds are currently light out of the north on the back side of the trough, while out ahead of it winds are light to breezy out of the south-southwest. Temperatures currently sit in the 80s to low 90s. Skies are a bit hazy from wildfires out west, and hi-rez models keep smoke in the region at least through Friday.

As the trough moves southeast towards more available moisture, a few CAMS show potential for isolated storm development near south central SD late this afternoon into early evening. CAPE values in the 700-1400 j/Kg range, coupled with 30-40kt 0-6km shear, could promote an isolated strong to severe storm if there is any initiation this afternoon. Main concern will be available moisture down there. Models do hint at a LLJ setup both overnight tonight and Friday night. For tonight, CAMS don't point towards any development tonight, given the dry air. Early Saturday morning may be more concerning, with better moisture advection, models do point towards a higher potential for overnight storms with a a chance for severe. Currently models show the best location for storms early Saturday morning around south central SD.

Upper ridge flattens out a bit over the weekend, prompting slightly cooler temperatures Monday through the remainder of next week, though still in the 80s. With a more zonal upper flow setting up, next week looks a bit more active with shower/storm potential. Especially the latter half of next week, as models point towards better moisture advection into the area.

AVIATION

(For the 18Z TAFS Through 18Z Friday) Issued At 1121 AM MDT Thu Aug 6 2026

VFR conditions are expected throughout the TAF period. Winds will shift to the northwest across much of the area this afternoon and evening as a weak front moves through the region.

UNR WATCHES/WARNINGS/ADVISORIES

SD...Red Flag Warning until 8 PM MDT this evening for SDZ322-327. WY...Red Flag Warning until 8 PM MDT this evening for WYZ314>317.